The Scale-throated Hermit (Phaethornis eurynome) is a species in the hummingbird family, Trochilidae.

It is found in or near Atlantic forest in north-eastern Argentina, south-eastern Brazil, and eastern Paraguay. It is generally fairly common, and consequently considered to be of least concern by BirdLife International and IUCN.

The supposed "Black-billed Hermit", described as P. nigrirostris, has turned out to be a mutant P. eurynome with an all-black bill.